Maturation stages of fruit development and physiological seed quality in Physalis peruviana

Abstract

In fleshy fruits such as the Physalis, in which the seeds are the main form of propagation, there is disagreement about the appropriate physiological stage for harvesting in order to obtain high-quality seeds. The objective of this study was to determine the stage of maturation of Physalis peruviana, using the colouration of the fruit and calyx, and relative to the physical aspect of the fruit and the physiological aspect of the seeds. The following five stages of maturation were studied: green calyx and fruit (A); green calyx and yellow fruit (B); yellowish-green calyx and yellow fruit (C); straw-coloured calyx and yellow fruit (D); straw-brown calyx and intensely yellow fruit (E). Physical evaluations were determined using the diameter, length and dry-weight of the fruit, and the 1000-seed weight and water content. The physiological characteristics of the seeds were determined by germination testing, seedling dry weight, germination speed index, seedling emergence in the field and emergence speed index. In Physalis peruviana, the diameter, length and dry weight of the fruit increased with the increase in physiological maturity. The maturation stage did not affect the percentage of germination or seed vigour in Physalis peruviana.